3-perfluoroalkyl-1 propenes and process for producing

ABSTRACT

This invention discloses the preparation of 3-perfluoroalkyl-1propenes with the perfluoroalkyl group containing three to fourteen carbon atoms. These compounds are formed by treatment of   D R A W I N G

United States Patent 1191 Knell et al.

3-PERFLUOROALKYL-l PROPENES AND PROCESS FOR PRODUCING Inventors: MartinKnell, 4 Possum Rd.,

Ossining, NY. 10562; Neal 0. Brace, 1202 Howard Cle., Wheaton, 111.60187 Filed: Sept. 1, 1971 Appl. No.: 177,091

U.S. Cl. 260/6533 Int. Cl. C07c 17/00, C070 21/18 Field of Search260/6533 References Cited UNITED STATES PATENTS 3/1959 Miller 260/6533 151 Oct. 22, 1974 5 7 ABSTRACT This invention discloses the preparationof 3-perfluoroalkyl-l-propenes with the perfluoroalkyl group containingthree to fourteen carbon atoms. These compounds are formed by treatmentof with zinc wherein R, is perfluoroalkyl, and R is lower alkyl, acyl,benzoyl or aryl.

5 Claims, No Drawings g the formula:

4 wherein R; is a long chain straight or branched perfluoroalkyl groupof the formula C,,F where n is an integer from 3 to 14 and morepreferably 6 to 12. There compounds are disclosed in Anello et al U.S.Pat. No. 3,576,858 issued Apr. 27, 1 971.

The present compounds are useful intermediates for application intextile finishes. lllustratively, the 3-perfluoroalkyl-l-propenes of thepresent disclosure may be converted to fluoroalkyl fumarates which maybe employed as textile finishes. Reference is made to E. K. Kleiner andM. Knell, US. Pat. application Ser. No. 720,370 filed Apr. 10, 1968 foremployment of the fluoroalkyl fumarates as soil repellents.

In the technique of this disclosure, the 3-perfluoroalkyl-l-propenes areformed by treatment of specific 3- perfluoroalkyl-Z-iodo-I-alkyl ethersor 3- point of economic consideration, R; desirably contains six to 12carbon atoms. R, groups-containing less than six carbon atoms do providesoil repellency in textile finishes. Nevertheless, due to industrystandards of high repellency levels, an additional fluorine content isdea suitable R group contains seven carbon atoms.

Pstflyorqsllsx ii dq-llallsy rs .W FPll QW 7 sults in terminalunsaturation. In contrast, the prior art teaches the treatment ofclosely related fluorinated iodoalkanes with zinc-results in a differentreaction,

namely replacement of the iodine atom by hydrogen (Haszeldine andSteele, J. Chem, Inc. 1953, I 199; Haszeldine and Steele, J. Chem, lnc.I953, 1592.)

CHCH OR The present process is directed to the treatment of thedisclosed 3-perfluoroalkyl-2-iodo-l alkyl ethers or esters with zinc toobtain terminal unsaturation rendering novelty to the present technique.A hydroxylic solvent may be employed in conjunction with the disclosedprocess.

DESCRIPTION OF THE INVENTION The present process employs the utilizationof starting materials comprising fluorinated iodoalkyl ethers and esterswith zinc. The fluorinated iodoalkyl compounds utilized in thistechnique are known in the art and may be prepared in accordance withBrace US. Pat. No. 3,145,222 and Brace, J. Org Chem. 27, 3033, (l962),namely: g

peroxide I t catalyst R Cf t -lCi-i OR In the present disclosure R; is astraight or branch chain perfluoroalkyl group containing three to 14carbon atoms, and more desirably six to 12 carbon atoms. v The reactionto produce the 3-perfluoroalkyl-l propene is carried out in the presenceof zinc. A hydroxylic solvent may be employed. Additionally a protondonor The Brace disclosure illustrates the principle that in reactingfluorinated iodoalkyl esters in the presence of zinc, reduction of thefluorinated alkyl iodide takes place, namely the replacement by iodineby hydrogen.

In contrast to known teachings utilizing fluorinated alkyl iodideconstituents and zinc, the present invention employs starting compoundswhich are closely re- 7 lated to prior art starting compounds but formsa reactant product which is totally unexpected.

SUMMARY OF THE INVENTION The present process may be summarized by thefollowing equation:

R cH cH a cn cz ca omzn whereih Rji aiong chain perfluoroalkyl groupeither straight or branched chain of the formula C,,F where n is aninteger from 3 to 14; R represents lower .alkyl containing one to fourcarbon atoms, lower acyl may be used in analogous fashion as prior artdisclosures but a different result is obtained in the present use withthe present selection of starting compounds. Suit- .239132 saslaqsgssissss@QH.

able solvents include methanol, isopropanol, cellosolves and ethyleneglycol, etc. Proton donor systems, if employed, can include hydrogenchloride, formic acid etc. and systems disclosed in the Haszeldine andSteele disclosures, supra.

In the reaction to form the 3-perfluoroalkyl-lpropenes utilizing thestarting compounds defined herein, namely and zinc, it is not directlyunderstood why replacement of the iodine with hydrogen does not takeplace under CH +Zn 05 r similar reaction conditions as the prior artemploying closely related fluorinated iodoalkanes. Nevertheless, inspite of the prior art indication and illustration of the replacement ofiodine by hydrogen in the presence of present invention the followingexamples are provided:

- EXAMPLE 1 i l ,1 ,2,3,3-pentahydro-Z-iodoperfluorol -decyl acetate19.0 Grams of zinc dust and 20 ml. of anhydrous ethanol are added to a500 ml. flask and stirred rapidly while ml. of 36 percent hydrochloricacid are added. The reaction mixture is heated to 60C and 50.0 grams of1 ,1 ,2,3 ,3pentahydro-Z-iodoperfluoro- 1 decyl acetate (preparedaccording to method of Brace, J. Org Chem. 27, 3033 (1962)) is addedwith 100 ml. of anhydrous ethanol. The addition of the acetate takesapproximately 45 minutes. The reaction mixture is continuously stirredfor an additional 2% hours and the temperature maintained at 60C.Thereafter the reaction mixture is cooled to room temperature, theunreacted zinc is filtered off and the product washed with 1500 ml. ofwater. The oily layer is dried over molecular sieve and then distilledthrough an 18 inch spinning band column; 19.6 grams of product boilingat 142l44C/760 mm. is obtained.

Preparation of ,3,3-pentahydroperfluoro-l-decene from,3,3-pentahydro-2-iodoperfluoro-1decyl hydroxyethyl ether A slurry of8.0 grams (.122 mole) of zinc dust in 80 ml. of acetic acid and 55 ml.of ether is heated to reflux with stirring and a solution of 50.0 grams(0.083 mole) of 1,1,2,3,3pentahydro-2iodoperfluoro-l-decyl hydroxyethylether (prepared from perfluoroheptyl iodide and allyl hydroxyethyl etheraccording to the method of Brace. J. Org Chem. 27,3033 (1962)) in 25 ml.of ether is added dropwise. Reflux with stirring is continued for about12 hours. The clear colorless solution is then separated from theunreacted zinc; water and sodium bicarbonate is added to neutralize theacetic acid. The ether solution is dried over anhydrous magnesiumsulfate and the ether removed with the aid of a water pump. The residueis then fractionally distilled through a short Vigreux column. The firstfraction, boiling at 4647.5 at 16 mm. pressure, weighs 22.3 grams and isshown to be 1,l,2,3,3- pentahydroperfluoro- 1 decene.

EXAMPLE 3 Preparation of Bis( 1,1,2,2,3,3-hexahydroperfluoro-l-decyl) Fumarate a) 1,1,2,2,3.3-Hexahydroperfluoro-l-Bromodecane 15.6 Grams of1,1,2,3,3-pentahydroperfluoro-ldecene are added to a quartz glassFischer Porter tube and brought to boiling to remove any possibletrapped air. It is then closed off, cooled to the temperature of liquidnitrogen and 7.0 grams of dry hydrogen bromide added. The reactionmixture is allowed to warm to room temperature and it is then placedcentimeters from a 250 watt UV light source for 4% hours. The excesshydrogen bromide is permitted to escape and the product is then washedwith 50 ml. of water to remove any trapped hydrogen bromide. It is thenwashed with 25 ml. of a 10 percent solution of sodium thiosulfate anddried over molecular sieve. Distillation yields 16.8 grams of productboiling mainly at 9596C./24 mm.

Analysis for C H BrF C H Br F Calc.: 24.46; 1.23; 16.27; 58.04 Found:24.31; 1.27; 17.50; 511.10

, EXAMPLE 4'" b) Bis( l ,1 ,2,2,3,3-l-1exahydroperfluorol decyl)Fumarate Analysis for C H F O H F Calc.: 30.78; 1.51; 60.87 Found:31.08; 1.62; 60.83

EXAMPLE 5 Preparation of l,1,2,3,3 pentahydro-2-iodo-perfluoro- 1decylphenyl ether (C 11 OCH CH1CH C F Allyl phenyl ether (Aldrich,13.4g, 0.100 mol), liodoperfluoroheptane (redistilled, bp /70 mm, r1 D1.3286; 49.6g, 0.100 mol) and azobisisobutyronitrile (0.456g, 0.00278mol) were charged to a Fischer Porter aerosol tube, cooled to 78,evacuated and filled three times with nitrogen, sealed and heated at 700for 21 hr. An orange, cloudy mixture formed, which was cooled to 20,filtered through a sintered disc into a distillation flask (62.5g) anddistilled in a two-foot platinum spinning band column (Column A).liodoperfluoroheptane (bp 36/l0 mm, n D 1.3308, 21.5g), allyl phenylether (bp 3910.20 mm, n D 1.5184, 4.72g) and the adduct (C H OCH CHICH CF bp 96-99/0.14 mm, n D 1.4245, 29.55g), a residual brown oil (4.0g) andtrap liquid (2.0g, n 1.3794, mostly C F 1) were obtained. The yield ofthe adduct was 89 percent, and conversion was 47 percent based onrecovered starting materials.

Analysis for C..,H,,,F,,10;

Ca1c.: C. 30.4);

EXAMPLE 6 Preparation of l .1 .2,3 .3-pentahydro-perfluorol -decene fromZinc powder (9.2g, 0.14 mol, 60-200 mesh size), was added to a solutionof 50 ml of ethanol and ml of 36 percent hydrochloric acid in a 500 mlr.b. flask. fitted with a paddle stirrer, refluxcondenser and droppingfunnel, and heated to 60. A solution of C H OCH CHICH C F, (28.5g,0.0470 mol) in ethanol (50 ml) was added during l hr at 60-70 whilestirring. A gray cloudy slurry formed with an exothermic reaction.Stirring was continued for 2.0 hr at 70 ;.5 ml of 36 percent HCl wasadded, and stirred for 2.5 hr at 70. The reaction mixture had separatedinto 2 layers. To the cooled reaction mixture, decanted from zinc, wasadded 200 ml of water, and the lower layer removed (17.1g, 88

percent crude yield). The aqueous layer was extracted Analysis for C HFm Cale: c, 29.35; H, 1.12; F, 60.49 Found: c, 29.52; H, 1.32; F 67.93

EXAMPLE 7 Preparation of t mcthikfisiitetteflustt kpe y acetate(cFabcFCl-lzCl-llCH O Ccl-w 2-Iodoperfluoropropane (29.6g, 0.100 mol),allyl acetate (10.0g, 0.100 mol) and azobisisobutyronitrile (0.328g,2.00 mmol) were charged to a Fischer Porter aerosol tube; after theusual procedure, the tube was heated at 700 for hr. Distillation inColumn A gave (CF CFCH -CHlCH O CClbp 70/4.3 mm, n D 1.4069, 34.60g (in3 cuts); an impure higher boiling mixture, bp 72-69/0.15 mm, n D 1.4292,1.05g, and a residue, 0.5g. The 78 trap contained two layers (5.0g),recovered (CF CFl and allyl acetate. The conversion to product was 87.5percent.

Analysis 1111 C,H,F,10, Cale; C. 24.26: Found: C, 24.09;

EXAMPLE 8 Preparation of 4-'l"rifluoromethyl-4,5 ,5 ,S-tetrafluorol-pentene (CF11 from (CF CFCH CHlCH O CCH (30.0g, 0.0756 mole) was addedslowly from a Varibor dropping funnel to a slurrly of zinc (10.0g,0.153g-atom) in oxydiethanol (diethylene glycol, ml), while stirring bya magnet in a total reflux, partial take-off distilling apparatusconnected to a Dry-Ice trap. The iodo acetate was.

v p.p.m. from tetramethyl silane as a doublet of doublets;

and for CH=CH at 5.05 to 6.25 p.p.m., as a multiplet. These data wereconsistent for (C .3)2CFCH CH=CH Analysis for C,,H,,F,:

Culc.: C, 34.30;

H, 2.40 Found: C, 30.76; H, 2.20

The volatility of the sample caused elemental analysis to be inaccurate.

EXAMPLE 9 Free Radical Addition of R,l (R C C C to Allyl Acetate;Preparation of 2-iodo-3-perfluoroalkyll-propyl acetate (R,CH CHICH O CCHPerfluoroalkyl iodide mixture was fractionally distilled and a solidresidue was obtained having the composition by glpc analysis: R11, R C FI, 11.5 percent; C, F l, 83.8 percent and C F I, 2.3 percent. There wereseveral unknown substances present 7 in small amount. This material wasused in the following preparation. R,l (64.6g, ca. 0.100 mol) andbenzoyl peroxide (0.484g, 2.00 mmol)were placed in a ml r.b. flaskfitted with a nitrogen inlet, reflux condenser, Varibor dropping funnel,and stirred by a magnet while heated in an oil bath. Allyl acetate(100g, 0.100 mol) was added dropwise during 35 min at 97-102 (inside),cooling as necessary to maintain reaction temperature at 100 fl. Heatingin the bath at 100 was continued for 3 hr, and allowed to standovernight. A solid mass of crystals formed, which would not distill 'at100 (12 mm pressure); m.p. (sinter 54) 56-59; ir showed 7C=O 1750 cm,heavy 'yCF and other bands antici pated for the adduct R,CH CHlCl-l OCCH A 5.0g portion of the product was recrystallized from ca. 50 ml ofligroine (6090 bp). Fractions collected were: (1 1.8g, mp 63-64; (2)2.5g (after chilling, and evaporation), mp 63-64; (3) 0.9g, mp 55"-58;(4) 0.8g, soft solid. VPC analysis of the mixture showed RCHgCHlCHzOzCCHgRFCgFm, percent; CgFn, 12.6 percent and C F- 76.6percent. After recrystallization R C,, F 4.8 percent; C F 83.0 percent.An nmr spectrum agreed with structure.

EXAMPLE Preparation of l,1,2,3,3-pentahydro-perfluoro-l-tridecene (C FCH CH=CH from 2-iodo-3-(pe'rfluorodecyl)- l-propyl acetate The crudeadduct (R,CH CHICH O CCH mp 5659, 37.3g, 0.0500 mol) was dissolved in 80ml of hot ethanol, and added during 25 min at 76-78 to a slurry of zincdust (9.8g, 0.15 g-atom), ethanol ml) and 36 percent hydrochloric acid(5m1). There was some exothermic reaction. After 1 hr further at 78 thetwo layers which had formed were poured into water (100 ml) andextracted with dichloromethane (100 ml). Three layers now formed. Thelowest layer was removed (14.6g), which solidified at room temperature;mp ca. 30. It was distilled under reduced pressure in a variable takeoff still without a column; bp 8599/9.0 mm, n D 1.3100, 8.5g. Solidformed in the still head (1.0g recovered), and remained in the pot flask(235g). The dichloromethane extract was washed further with dilutesodium sulfite solution, dried over MgSO, and distilled. Product, bp8893/9.0 mm, n D 1.3135, 5.2g was again obtained. (Total yield ofdistilled product 55 percent),A residue of 3.2g solid remained. An NMRspectrum agreed with structure, R,CH CH==H Addition of C F 1 to AllylBenzoate; 1,1 ,2,3,3-penta-hydro-2-iodo-perfluorol -decyl benzoate(C7F15CH2CHICH202CC6H5) Allyl benzoate was prepared from allyl alcoholand benzoyl chloride, bp 102104/13 mm, n 'D 1.5165 lit.*, bp 106/l2 mm,n D 1.5174. A Fischer Porter aerosol tube was charged with allylbenzoate (16.2 g, 0.100 mol), l-iodoperfluoroheptane (49.6 g, 0.100 mol,and azobisisobutyronitrile (0.328 g, 2.00 mmol). After the usualprocedure the tube was heated at 70 for 12 hr, the reaction product (twolayers) filtered through a sintered disc and distilled without a column,using a variable take-off head. C F, l (15.1 g, percent recovery) andallyl benzoate (1.7 g) were removed. The residue was placed on column Aand more allyl benzoate (1.7 g, total 21 percent recovery), C,F, CHCH1CH O C H bp 104-107/0.30 mm, n D 1.4290, and bp 11 l-1 12/0.25 mm, n-"D 1.4286, 49.96 g (76 percent conversion, 96 percent yield, based onrecovered allyl benzoate), and a residual oil (6.8 g) were obtained, Theproduct turned solid when cooled to 10.

Hurd and Filuchionc. J. Am. Chem. 500.. 61, 1156 (1939); Tommilu. Ann.Acad. Sui.. Fcnn., [A], 59, No. 3, 7 (1942); Bcilstein, Vol 1X, Elll. p.402.

EXAMPLE 12 Preparation of 1,1,2,3,3-pentahydroperfluorol -decene fromC7F15CH2CHICH2O2CC6H5 Using a procedure similar to that for (CF C FCHCH'-=CH a slurry of zinc dust (9.2 g, 0.14 g-atom) and 2,2-oxydiethanol(20 ml) washeat d to 1 15" -122 (inside) while C F, CH CHICH O CC H(35.0 g, 0.053 mol) was added during a half hr. After the first 15 min,a water pump was attached to reduce the pressure; C F CH CH=CHdistilled, bp 86-88/1 10 mm, n D 1.3076, 18.5 g. After all the olefinwas obtained the pressure was reduced further during 20 min to strip anyremaining product from the pot liquid. The final pot temperature was 138at 10 mm pressure. The cold trap contained 1.4 g; total 19.9 g (91.5percent yield). The product was dried over a little Drierite. A check byglpc (6 ft Carbowax 20M, 10 percent on Chromosorb W, at 68 and 15 psihelium pressure) showed one peak at 1.2 minutes. An infrared spectrumwas identical to that of C F, Cl-l Cl-l=Cl-l previously prepared.

EXAMPLE 13 Free Radical Addition of l-lodoperfluoroheptane to AllylPropyl Ether; Propyl 2-1odo-l,1,2,3,3-pentahydro-perfluoro-l-decyl Ether(C F, CH CHICH OCH CH CH l-Iodoperfluoroheptane (49.6g, 0.100 mole),allyl propyl ether (15.0g, 0.l50 mole, Chem Samples Co., 97 percent) andazobisisobutyronitrile (0.328g, 2.00 mmole) were charged to aFischer-Porter aerosol tube. After the usual procedure the tube washeated for 12 hrs. at 70. The colorless clear mixture became cloudy. Itwas filtered through a sintered glass disc and distilled in column A. Amixture of C F, l and allyl propyl ether (657g, n D 1.3905), and C F, l(9.27g, n D 1.3300) were recovered; C F, CH Cl-llC1-l -OCl-l Cl-l Cl-ldistilled, bp 81-83/0.85 mm, n D 1.3767, 42.65g (71.5 percentconversion). A residue of 1.0g remained. The trap contained 2.50g ofstarting materials (n D 1.3500).

Analysis for C H F OI: V

Calc.: C. 26.19; H, 2.03; F, 47.81; 1, 21.29 Found: C, 26.50; H. 2.10;F, 47.08; 1, 21.31

EXAMPLE 14 hour under 60 mm pressure. The distillate consisted of twolayers (19.4g); the -78 trap liquid (2.86g) also formed two layers.After drying over MgSO distillation in column A gave the following: l,bp 44/6O mm, (n 'D not taken), 1.40, 2 layers; 11, bp 68-73 /60 mm, n D1.3143, 0.40 g; 111, bp 73-74/60 mm, n 'D 1.3084, 4.20g,C F, CH C1-1=CH1V,bp 74/60 mm to 56/21 mm, n D 1.3070, 4.24g, C F,,,CH CH=CH V,

bp 94/21 mm, n D 1.3155; 080g; V1, bp 94/21 mm.

to 87/6 mm, n D 1.3361, 0.95 g; and VII, bp 85/l.1 mm, n D 1.3694,3.75g, recovered C F CH CHlCH- O(Cl-l CH There was no residue. Theinfrared spectrum of fraction V11 was identical to that of the startingmaterial. The retention time of the peak in glpc analyses of fractions111 and IV was identical to that of C F CH CH=CH previously prepared.The conversion to C F, CH CH=CH was 34 percent; the recovery of startingmaterial was 12 percent. Undoubtedly more starting material remained inthe reaction mixture which could have been recovered. Nevertheless,reaction of this ether appeared, to be more sluggish than that of thebenzoate or acetate esters.

What is claimed is: 1. A process for the preparation of 3-perfluoroalkyll-propene which comprises treating R CH CIIHCH OR I where Rf is CnF n isan integer from 3 to .14 and R is lower alkyl, lower carboxylac'yl,benzoyl or aryl, with zinc in the presence of an alkanol of one to threecarbon atoms, a glycol of up to three carbon atoms, ethylene glycol ordiethylene glycol.

2. The process of claim 1 wherein n is an integer from 6 to 12.

3. The process of claim 1 wherein R is lower alkyl.

4. The process of claim 1 wherein R is lower carboxylacyl.

5. The process of claim 1 wherein the reaction is effec'ted in thepresence of an acid.

I A'IRS lA'lIJNl OFFICE cma l u lcATls 01 CORRECTION Patent: No. 3,88,735 Dated October" 2, 97

Inventor) MARTIN KN'ELL ET AL It: is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

In column 10, 1, lines 12 and 13, after the phrase "three cerbon atoms,delete "a glycol of up to three carbon atoms, ethylene glycol ordiethylene glycol" and insert therefor ethylerle glycol or diethyleneglycol at a temperature of 60C to the reflux temperature of th e systemSigned and sealed this 31st da y-of December 1974.

(SEAL) Attest:v

I IcCOY M. GIBSON JR. c. :mesmu mm? Attesting Officer Commissioner ofPatents

1. A PROCESS FOR THE PREPARATION OF 3-PERFLUOROALKYL-1PROPENE WHICHCOMPRISES TREATING
 2. The process of claim 1 wherein n is an integerfrom 6 to
 12. 3. The process of claim 1 wherein R is lower alkyl.
 4. Theprocess of claim 1 wherein R is lower carboxylacyl.
 5. The process ofclaim 1 wherein the reaction is effected in the presence of an acid.